increasing heap size of pico2

[task-jp]

Hi, I'd like to increase the size of heap defined for Pico2 as below to 500k or slightly less.

https://github.com/slint-ui/slint/blob/master/examples/mcu-board-support/pico2_st7789.rs#L31

const HEAP_SIZE: usize = 200 * 1024;
static mut HEAP: [u8; HEAP_SIZE] = [0; HEAP_SIZE];

Current value 200k may come from pico that is with 264kB on-chip SRAM. Pico2 has 520 KB.

[ogoffart]

Yes, that makes sense.
Maybe something like 400 would be alright to also leave extra room for the stack and data
(But I don't have a pico2 so i wouldn't be able to test what is a good limit)

[task-jp]

Thanks. I've created the PR for that #8484
The size of stack and data depend on application that use this feature. I agree that 400 is good in general.